Leaflets will be handed to mourners at the funeral urging them to register as potential donors and highlighting the Grown Ups Congenital Heart Patients Association.

Sammy had fought against heart disease from birth, undergoing major operations from the age of three, said Mr Edwards.

“It was enormously hard for her at times but she was very brave. She never said, ‘Why me?’ or played on it, and was an example to everyone.

“She lost her granddad in November and that upset her. He was ill for several years but she was his inspiration. She had this amazing smile and just lived life to the full.”

On December 9, she was put on an national urgent list for transplant and had 11 potential donors. But none proved a suitable match.

She was living in Newcastle, awaiting treatment at the specialist centre, with her family making the lengthy journey to be by her side. Medics put her on revolutionary drugs to suppress her immune system.

But despite enormous efforts over Christmas she got worse.

Mr Edwards said: “She knew she was fragile but rather than just take the palliative pain relief she chose to fight on. She chose life. But that struggle was the reason she went downhill so fast.”

Mr Edwards was at her bedside on January 14, when she died.

Some 450 people have paid tribute to her on a dedicated Facebook page set up by school friend Joanna Tapscott, 21, of Connah’s Quay.

Joanna said: “She's the bravest person I've ever met she would smile all day every day through school. She wouldn't let her pain show.

A Mass was read at her former school in her memory last week.

A statement on the school website said: “Samantha was a lovely young lady and fondly remembered at St Richard Gwyn. We pray for her family at this time of sorrow.”

The family praised the efforts of medical staff from Liverpool’s Alder Hey through to Newcastle’s Freeman Hospital.

Mr Edwards is already planning a sponsored walk along Offa’s Dyke to raise money for the two charities.

He said: “We all love walking in our family. One of our favourite memories is walking up Moel Famau together.

“I would normally end up carrying her up there on my back, which she loved.”